In Missouri, we have signs on the highways that say, "Lights on when wipers required." I turn mine on any time the light quality makes it hard to see but many people don't and I haven't seen the cops enforce the rule. I don't think it's a matter of forgetting to turn them off later & running the battery down. I haven't driven a car or pickup that didn't beep if you leave the lights on for many years. I know the 1999 Ford Ranger pickup beeps and I believe my daughter's 1997 Chevy Cavalier beeps.
Motorcycles are required to have their lights on all the time.